Unusual Rainfall in N.W. Province of Sri Lanka.

Rainfall during the last couple of months in N.W.Province of Sri Lanka in general and the village of Paneyadi in particular has been very unusual.
We have had about 500mm during the last 2 months where annual average is around 1200+ mm most years. Normally we can expect a maximum of 200 mm for April and May. Records for the last 10 years back it up.
I did not see any predictions about this major shift even though as a Coconut farmer it's welcome by me. Disaster for Cashew growers at this time of year.
Any idea of major reasons for this unusual rainfall?